HDR using one picture only ???? Worth it?

[kevinbythebeach]

Ok i tried it using one photo...and I converted it to 16 bit and played witht he sliders and all...
But i didnt see any changes that i think I cant make using other PS options.....
I understand the usign multiple pics at differnt exposures to combine and make a betetr pic theory.

But if you only have one pic is it worth the time? Am I missing something?

[Davey]

HDR from 1 pic is impossible technically speaking. I know there is debate about this but it arises from misunderstanding tone mapping and hdr etc, simly put how can you increase dynamic range of a single ldr image without putting more range data in. Also you need a scene/subject where it's impossible to encompass the whole range in 1 single capture for it to be hdr image since 2 or 3 combined captures in of a standard scene with range that can be captured in 1 has no extra range either due to input data being identical.

Tone mapping or hdr processing workflow on the other hand might be useful even if it is starting and ending with a ldr image. Eg. For artistic reasons or to cut corners on steps that might be better result processed manually but for large batches/short on time situations it simply isn't possible. So I'm not saying hdr workflow (or rather some steps of like tonemapping) doesn't have it's place for other applications (although there is better ways without the drawbacks when it comes to things like exposure tweaks IMO).

[Grinder]

I think Davey is splitting hairs. While HDR and Tone Mapping are two separate processes NORMALLY you do one AND the other. In America when someone says I need a Xerox something they mean I need to PRINT something. In Texas when they go to a resturant and say I want a Coke they are asked what KIND of Coke, Pepsi? Mountain Dew? Dr. Pepper?

BUT - to answer your question. It sure is possible and worth it. Below is a 1 RAW photo. In fact I do most of my "HDR" work with One RAW photo. You just have to experiment with what works and what does not. You have less leeway on light brilliance and shadows.

The "Single shot RAW - Wisconsin Capitol" thread is also one photo (of course).

[David]

Hi Guys - I've posted on this matter in the past. The term that seems to be generally used for processing one image via HDR software is "pseudo-HDR". Rod's shot is a good example of pseudo-HDR. In my view, there is nothing wrong with doing this as a post-processing technique for creative or realistic purposes. In my hands I've found that both highlight and dark tonal areas can be improved if you work from the original RAW file.

Davey is correct in that for the full dynamic range of a scene to be captured and then tone-mapped you have to have (a) a scene where there is a dynamic range outwith the range of a single exposure, and (b) several exposures to capture that range adequately.

Cheers

David

[Grinder]

Exactly - 1 RAW shot will work if the total range is not that great.

BTW - I'm going to change my name to . . .Dave.

[Dave Humphries]

BTW - I'm going to change my name to . . .Dave.

It works for me and I didn't even have to change it (much)

[Grinder]

Is EVERYBODY in the UK named Dave? Is it High DAVE Range Photography?

[Colin Southern]

I think Davey is splitting hairs. While HDR and Tone Mapping are two separate processes NORMALLY you do one AND the other.

Not at all - he's quite right.

Of recent there seems to have been almost a "mutation" of peoples perception of what HDR is; almost by definition, it's an image that has a dynamic range that's too big to handle by conventional techniques - so to cope with the range we hit it with a 2-part process ...

1. We capture bracketed exposures to capture the full dynamic range of the scene, but that leaves us with the problem of what to do with it; no monitor can display it in that form, and it's not possible to print it either.

2. So something has to give - and that something is the high dynamic range is compressed (not necessarily in a linear way) into something we can present to an output device in the form of tone mapping, which - if done in a certain way - gives rise to a popular look that many have (unfortunately) learned to associate with being what a HDR image looks like.

So whereas it's possible to tone map and process a single exposure to look like what true HDR images may look like if processed in a certain way, it still doesn't make it an HDR image. Keep in mind that HDR NEVER refers to the output form as that is always limited to whatever our monitors or paper can display (a few stops at best) -- it refers to the dynamic range of the source; if that happens to tone map into something that has a certain characteristic look then so be it. If the above example was shot with a single exposure then it's not HDR. As an example, here's one that IS HDR, but you probably wouuldn't know it because it's not processed in the typical manner that's often misassociated with being HDR ...



We discussed it quite extensively a few months ago here if your interested.

[Davey]

Everyone in the UK called Dave? Of course not! In my experience I have found only around half of us are, the other half are called steve The odd other name slips through but mostly steve and dave, I'm yet to figure this out.

I personally like a lot of the unrealistic tone mapping styles I see and find it can add character to an otherwise mundane image (although admittedly it can be over used or used where another style is more ftting but that's true of many things and not just in photography, ketchup on noodles for instance (a pet hate of mine hehehehe, it has it's place.........but not on noodles)).

I can be a bit over rigid on technical things sometimes and have always been black and white on a few things when it comes to definitions and think sometimes popular opinion can skew actual facts (like the word droll taken to mean downbeat when it's the opposite, [cue rant on degeneration of english] ).

I do think the hdr thing is not really splitting hairs though. However seperating tone mapping from the process maybe would be as although it is technically discrete process which has nothing to do with HDR not many (outside of raytracing community at least) create a HDR image from several LDR ones and leave them as that but go the tonemap step further to make it into an LDR one again so it can be viewed as intended (ie.a high range scene outside capture and reproduction/display limits tonally compressed into possible limits).

[Grinder]

My point is that have you ever seen anybody Tone Map WITHOUT running the photo through a piece of software that also creates HDR?

Have you ever seen anybody create an HDR photo and then is THAT without further processing?

This is a High Dynamic Range forum which includes Tone Mapping. Perhaps we need a Tone Mapping or Tone Compressor forum??

If you buy a book (I hav e3 now LOL) on HDR it is mostly talking about Detail Enhancing or Tone Compressing multiple or single RAW photos.

So while Davey is correct "technically" I believe it is silly to draw a distinction between pseudo-HDR and true HDR.

And that is all I'm going to say because it is a silly argument either way and gets no one anywhere.

BTW - I WISH I could see the photos here. Locked out for most photos at work. All I see are a . I think photobucket is blocked.

[Davey]

You can get tonemapping plugins for remapping colours in ldr images for style reasons that give same effect so I have seen that. I personally think it's an important distinction because hdr is misunderstood and my background for the past 10 years has been design and 3d and hdr in rendering/cgi is very particular and in many cases hdr images are generated and not tonemapped or processed further. There are many applications of it and tonal compression for realistic display of an otherwise problematic to reproduce image in photography is only 1 of those . So for me it's very important to know exactly what hdr is, and as far as photography alone goes I think people can get more out of it or know more ways to achieve an effect (and thereby avoid drawbacks) if they understand technically correct term.

Like I say I like your images and the artistic surreal style and understand why HDRs meaning has been blurred somewhat. I do think it important that such myths are debunked though, not out of a need to be right or correct but mainly for the reason if people misunderstand something they cannot get as much out of it. For instance imagine being able to get the exact stylistic tonemapped look without the issues of ghosting, saturation issues, raised noise due to pushing single capture global exposure further than ideal etc etc. Knowing the exact nature of the beast makes it easier to get the most or to chose the best tool for the job I find.

Lastly I need to clearly state (although have in previous paragraph but just to be sure) this isn't one of those I'm right you're wrong things, I genuinely feel it's helpful to point to the correct method. If I thought the misunderstanding was more beneficial to others then I'd probably recommend that even though it was technically wrong, in much the same way many things you may learn at a-level you later learn at degree level isn't technically true but is more correct to teach as it serves it's purpose in helping avoid rather than create confusion and aids learning rather than obstructing it. Of course this is just my opinion and for every man who agrees there is at least one who doesn't, everyone has choice and that's the way it should be so if you don't agree with my view then I say NO!!! Just kidding hehehe it's cool with me either way.

[Grinder]

I do think it important that such myths are debunked

Fair enough! I know JUST enough to make myself eat crow at times so while I might disagree it does not mean I'm not listening and changing my mind.

[Colin Southern]

My point is that have you ever seen anybody Tone Map WITHOUT running the photo through a piece of software that also creates HDR?

I think part of the problem is that many seem to have a mindset that "you create an HDR image" whereas in reality what's happening is a NORMAL dynamic range image is being created from a high dynamic range batch of images. What makes an image HDR is the source images, not the resultant image (which if it were truely HDR, wouldn't be able to be displayed properly).

The "look" given to these (or any other) images really doesn't enter into it; as I've mentioned earlier that look can be photorealistic or anything else, but these looks are independent of the dynamic range of the source image(s).

[OldCrow]

Grinder asked "Is it High DAVE Range Photography? "

Apparantley. My real name is Dave too. But I'm an American Dave.

[David]

Hi Guys - Interesting debate. I think everyone's correct, but the arguments are from different stand points. From a technical view, I'm with Davey because there can be issues in say medical and forensic photography where getting the details of the process absolutely correct could be vital. I'm also with Rod from a stylistic view because you want to be able to use these techniques creatively without worrying about technical detail or whether you need 1, 2 or 10 images. So you're all OK.

BTW, all us David's, Davey's, Dave's are profoundly grateful we're not from the Land of Oz where everyone is called Bruce!!

Cheers

David

[Colin Southern]

I'm also with Rod from a stylistic view because you want to be able to use these techniques creatively without worrying about technical detail or whether you need 1, 2 or 10 images. So you're all OK.

Hi David,

Just so the "HDR Look myth" doesn't continue to grow and prosper ...

... I still think it's worth labouring the point that the "stylistic view" is just a processing workflow that can be achieved regardless of whether or not the source was a true HDR collection of bracketed shots or one shot, so HDR really doesn't enter in to it. Or put another way, HDR images don't have to look like that -- it's a processing choice that can be applied to ANY image, it's not an HDR technique or requirement - people have just unfortunately associated the two as always going together to the point where many are now saying that photorealistic HDR images aren't HDR because "they don't have that look", eg

[David]

Colin - I agree. HDR imaging has been growing apace and many practitioners are, perhaps, not aware that tone-mapping can give photo-realistic results. Some of the TMO's I've investigated in the Qtpfsgui posts are designed to give only realistic images (for better or worse). Others, particularly Manntiuk and Fattal operators can give some smart creative images as well as realistic effects. I think over the next year or so we'll see a division of terminology in HDR imaging with phrases such as "pseudo-HDR", "creative HDR", "photorealistic HDR" or similar being more widely adopted and understood.

Further, I agree that the use of the term HDR when LDR is actually meant has become widespread, and I'm guilty of doing it. There are no actual HDR images, they are all LDR images from TMO's. Probably this is why the original authors in this field, such as Debevec and Robertson, refer to High Dynamic Range Maps for the HDR "images" or files that are created.

Cheers

David